Researchers off Hawaii’s Kona coast on Friday documented a rare sighting of killer whales, including at least two that were playing host to hitchhiking remoras.

Killer whale with at least five remoras hitching a ride. Photo Robin Baird/Cascadia Research Collective

There were four individuals in the group: a male, an adult female, and two sub-adults. Three of the four were outfitted with satellite tags, and a biopsy sample was collected from one of the cetaceans.

Cascadia Research Collective stated on its Facebook page that this was only its third killer whale encounter in the 14 years the group, which is based in Olympia, Wash., has been conducting studies in Hawaiian waters:

Today off Kona we encountered a group of four killer whales! This individual has a number of remoras on it (photo (c) Robin W. Baird) There were four individuals (one male, one adult female, and two sub-adults), and we were able to deploy satellite tags on three individuals to track their movements, and collected one biopsy sample for genetic studies. This is only our third killer whale encounter in Hawaiian waters in the 14 years we’ve been undertaking research here, and the first time we’ve tagged killer whales in Hawaii. Needless to say it was a good day. We’ll be posting more photos and information on the encounter and other encounters in the last few days at www.cascadiaresearch.org/hawaii/OctNov2013.htm although probably not till tomorrow.

An adult female and a sub-adult. Credit: @Robin Baird/Cascadia Research Collective

“These are the first satellite tags we’ve deployed on killer whales in Hawaiian waters, and we think the first tags deployed on this species in the tropical Pacific, so we are excited about learning where these whales spend their time,” Cascadia stated on its website.

The 15-day research project ended Friday, but some of the scientists went back to sea on Sunday and re-located the four killer whales, plus three others, and witnessed a predation event involving a thresher shark.

Cascadia also posted a chart showing the movements of two of the three tagged killer whales: